Which peptides are being studied for weight control?
Updated: 2026-09-09 · GLP-1 and weight
Short answer
The most studied group is incretin analogues. Semaglutide acts on the GLP-1 receptor; tirzepatide acts on GLP-1 and GIP; retatrutide adds a third pathway, glucagon, and is not approved yet, although its phase 3 programme is already well advanced. Other molecules such as cagrilintide are also studied, working through a different, amylin-based mechanism.
In plain English
- GLP-1: lowers appetite and slows gastric emptying.
- GLP-1 + GIP: dual incretin mechanism.
- Triple agonist: adds the glucagon pathway; not approved yet, phase 3 already reported.
- Amylin analogues: another satiety route, in development.
What we know
- Semaglutide and tirzepatide have large clinical trials and regulatory approvals.
- Retatrutide is not approved; its manufacturer reported positive phase 3 results and says it plans an FDA submission in the first quarter of 2027.
What we don't know yet
- Long-term head-to-head comparisons and how durable results are after stopping treatment.
Sources
External links to official sources or peer-reviewed studies.